James m



(modem J. M. DODGE. Chain.

228,735- Piented June 15,18.

Jjigi g lm d w- 9m 5%, r V g UNITED STATES PATENT OFF CE.

JAMES M. DODGE, OF NEW YORK, n. Y.

CHAIN.

SPECIFICATION forming part of Letters Patent No. 228,735, dated June 15, 1880.

Application filed May 1, 1880.

ranged alternately singly and in pairs, with the ends of each single plate pivoted between the ends of the pairs of plates, had been made with the ends of the single plates or links closely confined laterally between the adjacent sides of the plates arranged in pairs, and with a pintle or pivotal bar passing through the adjacent ends of the three plates, and serving both as a rivet to hold the coupled plates ends together laterally and as a pintle or axis upon which the single plate might freely turn to give to the chain the necessary degree of flexibility; but in all such chains the parts have been greatly lacking in strength and durability at and in the vicinity of the joints or points of articulation.

My invention has for its object to overcome these defects of this class of chain and provide for use a chain in which, while the alternate single bars or link shall be articulated or hinged at each end between the double links or pairs of bars, the parts of the chain at and in the vicinity of the joints shall be as strong as at other points and shall possess a much greater capacity to wear than can possibly exist in chains of this class involving the principle of construction heretofore employed; and to these main ends and objects my invention consists in forming or providing the latorally-confining pairs of bars (or double links) in the vicinity of their ends, and on the adjacent faces of said bars, with projecting curved bearers, and the confined or intermediate ends of the single bars or links with boss-like projections, the said projections being adapted to work against the said bearers when the parts of the chain move relatively about their rivets as axes of motion, and the conjoint actions of the combined parts being such that all the frictional wear comes on the said projections (Model) and bearers, (Where they work together,) whereby, by reason of the capacity to have these wearing-surfaces of comparatively great extent, the parts will stand at and in the vicinity of their joints a much greater wear and strain with a given amount of stock to the chain than chains heretofore made could possibly bear, all as will be hereinafter more fully explained.

To enable those skilled in the art to make and use my invention, I will proceed to more fully describe it, referring by letters to the accompanying drawings, in which- Figure 1 is aside view, Fig.2 an edge view, and Fig. 3 a longitudinal central section at the line :0 0c of Fig. 2, of a flat-bar chain made according to my invention. Figs. 4, 5, and 6 are similar views of a chain also embracing my invention, but in a modified form, while Figs. 7, S, and 9 are similar iews of a chain, showing still another modification of my said invention.

In the several figures of each form of chain shown the same part will be found designated by the same letter of reference.

In Figs. 1, 2, and 3, A represents the singlebar link, and B the double-bar link.

In a chain such as here shown each singlebar link is made, as represented, with a sort of cylindrical enlargement or double hub-like laterally-projecting bosses, a a, at each end, and this enlarged end portion of the link is centrally perforated atb, for the accommodation of the rivet or pivotal cross-bar c of the double link B. The latter is made, as seen, of two similar fiat bars or plates, each of which has at each end a curved rib-like projection, 07, on its inner face or side, and also has two similarly-shaped projections, e and f, located also on the inner face, but intermediate of the projections d, and so as to form with the latter two pairs of circular ribs, arranged each concentrically to the axis of motion of the articurivets, or they may be materially smaller in diameter than. said perforations b. In the former casethe rivets will, to some slight extent, share in the wear and strain to which the parts may be subjected in the turning of the'links at the joints and in any pulling strain on the links, while in the latter case such wear and strain will come wholly on the projecting journallike portions act of the single links and the bearers d of the double-bar links.

It will be understood that in achain having the parts made and arranged together in substantially the manner shown and described the wear and strain, instead of being borne wholly by the rivets or pivotal studs 0, as usual in chains of the class to which my invention belongs, come upon the boss-like projections a and the rib-like curved projections d, and that since such portions to and (I may be made of a much greater size circumferentially (or diametrically) than it would be possible to make the studs 0 without destroying entirely the strength of the side bars of the double links, a chain made according to my improved plan of construction will necessarily be vastly stronger than, and can endure more wear and tear and strain at and in the vicinity of the joints than, the chains of the same class heretofore made.

Of course, the single-bar links should, as usual, he made proportionately thicker and stronger than each of the side bars of the links which are double, and all the parts should be proportioned to get the greatest degree of strength with the least amount of stock; and the shapes of the various parts and the designs of the links and chain may be varied without changing the principle of construction I have explained as giving to my improved chain its advantages over those heretofore made.

At Figs. 4c, 5, and 6 the chain shown varies from that just above described in the particular only of having annular rib-like projections s on the inner faces of the bars of the double links and of having the perforations Z) counterbored, as seen at 0, for the accommodation of said projections 8, while in the modification of my invention shown at Figs. 7,8, and 9 the single links are made with differently shaped and sized projecting Illli)1lk6 portions, as seen at m, and the side pieces of the double links, instead of having curved bearers, such as seen at d in the preceding figures,

have at either end of each circular enlargement n, in the inner face of each of which is a circular recess of an extreme diameter less than the width of the side bar, and conforming in shape interiorly to the external conformation of the projecting boss or enlargement m of the single-link bar. I

In some forms of my improved construction of chain portions of the projections on the inner faces of the double-bar links may be dispensed with without materially changing the principle of construction or losing any of the main advantages in use of the chain. For instance, in forms such as shown from Figs. 1 to 6, inclusive, the projections e and f might be omitted, and in the form shown at Figs. 7, 8, and 9 correspondingly-located portions of the circular projections m might be omitted. For chains for some purposes it may, however, be desirable and advantageous to retain all these devices.

As in the case of the old form of chain of this class, my improved chain may, of course, be made with a duplication of parts widthwise of the chain to produce what are sometimes more properly called chain-belts.

Having now so fully explained the nature of my invention and best forms now known to me in which to carry out said invention as to enable those skilled in the art to make and use my improved chain, and wishing it to be understood that I do not desire to limit my claim of invention to any precise forms or details of construction embodying the principle in which, as I have explained, my chain differs from those of the same class heretofore made, what I claim as new, and desire to se cure by Letters Patent, is

In a chain composed of alternate single and double bar links, (or an aggregation width wise ofsuch alternate single and double links,) the combination, with the bars or plates composing the links, of curved projections to form the bearings at the articulations of the links,

and take the wear and strain usually enforced upon the studs or bars that perform the office also of tying together the bars composing the double links, all substantially as set forth.

In witness whereof I have hereunto set my hand this 26th day of April, 1880.

JAMES MAPES DODGE. In presence of- ALBERT M. DAY, BURRoUs M. SAUNDERS. 

